Police believe far more road accidents are caused by drivers using their mobile phones at the wheel than is shown in official records, a new investigation reveals.

Specialist collision officers say dangerous drivers are evading justice because police lack the powers and resources to probe whether a mobile phone may have caused an incident.

Phones are only currently routinely seized following an accident that results in fatal or life-changing injuries.

If police can’t detect the full extent of this behaviour then we are missing an important part of the investigation pictureDr Paul Pilkington, UWE Bristol

A study found that three quarters of collision investigators who were interviewed said they had been unable to report the full proportion of road accidents linked with mobile phone use within the last year.

They said that the figures would jump dramatically if they were able to properly investigate all accidents thought to be phone-related.

A similar percentage said they were desperate for roadside technology that allowed instant examination of mobile phones in the immediate aftermath of a collision.

So-called “textalyzer” devices already exist, and authorities in some US states are currently debating whether to provide them to traffic officers.

Dr Paul Pilkington, a public health expert at University of the West of England, Bristol, where the study was conducted, described the constraints limiting investigators as a “massive problem”.

“It leaves a significant gap, not only in terms of enforcement but also monitoring of the role of phones in crashes,” he said.

“The result is significant under-reporting of the role of mobile phones in road traffic crashes, as well as inadequate justice for the victims of those affected by the actions of drivers using their phones behind the wheel.

“If police can’t detect the full extent of this behaviour then we are missing an important part of the investigation picture.”

An RAC survey published in September revealed that the number of motorists illegally using their mobile phones while driving was on the rise.

Nearly a third of drivers who took part admitted they had used a handheld phone behind the wheel, compared with eight per cent in 2014.

Tougher punishments for offenders will come into force next year, with penalty points doubling from three to six and fines doubling from £100 to £200.